Network appliances, as discussed herein, are communication devices that can be used to provide networking capability by offering a communication platform, which can be composed of one or more components, that includes hardware to which cabling can be connected to form a network with other devices also connected to the cabling. A network appliance can be implemented to provide specific networking functionality according to a chosen topology or protocol, such as functionality in accordance with implementing an Ethernet network. In general, a network appliance can provide one or more input/output (I/O) connection points that can be used for communications with other devices. Typically, some number of I/O connection points can be network cable receptacles that can permit connection of network cabling to the network appliance to contribute to implementing a network.
Network cable receptacles that can be provided by a network appliance are often physically labeled with identifiers that can indicate a function or characteristic of the network cable receptacle. For example, if the network cable receptacles are used to contribute to implementing an Ethernet network, the associated physical labels may include identifiers such as “Ethxx,” where the “xx” portion represents a number that uniquely identifies a given network cable receptacle on the network appliance. Such physical labels can be important as assisting in permitting other Ethernet devices to be properly connected to the network appliance, since persons such as network technicians may look for and expect to see certain physical labels for Ethernet network cable receptacles to which Ethernet network cables are to be connected.
The network appliance also typically includes an operating system (OS), which may be implemented as a so-called “open source” OS, an example of which is a Linux-based OS. Some examples of OS implementations that are each a Linux-based OS include Red Hat Enterprise Linux (RHEL) and Novell/SUSE Linux Enterprise Server (SLES). The OS performs a number of functions with respect to the network appliance, such as, for example, executing program code to locate or discover hardware devices, as well as providing for the configuration or setup of such discovered hardware devices. Such hardware device discovery is typically achieved with commands provided by the OS to certain hardware addresses to prompt a response from each hardware device installed at such hardware addresses.
One type of hardware device that a network appliance may implement and that the OS can discover is a network port. A network port is a hardware device that can be used to implement a network connection between the network appliance and another device connected to the network appliance with a network cable. The network port can be connected to a network cable receptacle, such as is discussed above, and can provide signaling over such a network cable connected to the network cable receptacle to contribute to implementing a network. Upon discovering a network port as a hardware device, the OS can provide a configuration to permit the discovered network port to operate in accordance with an expected behavior. For example, the OS can determine that the discovered network port is an Ethernet network port, and can thus provide a configuration to permit the Ethernet network port to operate in accordance with the Ethernet protocol. As part of providing such a configuration, the OS may provide a unique internal logical name for each discovered network port, so that the OS and other software programs can uniquely refer to the discovered network ports by their respective logical names.
There is no OS convention or standard for associating a specific logical name with a specific hardware device. Typically, in a network appliance, the OS assigns a logical name that depends on the type of hardware device and the order in which the hardware device is discovered relative to other discovered hardware devices. Thus, for a group of network ports in a network appliance, each network port would typically be assigned a logical name in accordance with the order in which the OS discovers and configures each of the network ports. For example, the logical names assigned to a group of Ethernet network ports may take the form “Ethxx,” where “xx” represents a unique number for each discovered Ethernet network port, which number is typically assigned in linear increasing order, in accordance with the order of discovery of each Ethernet network port. The order of discovery of hardware devices, such as network ports in a network appliance, may be impacted by the arrangement of the hardware devices in the network appliance, the OS type, OS vendor, OS version, or other factors that can influence the OS in the discovery of hardware devices. Accordingly, it can be difficult to predict the OS discovery order and thus the logical names that will be assigned to given hardware devices.
One drawback associated with the difficulty in predicting the discovery order of hardware devices in a network appliance is that the assigned logical name may not match a physical label for a given hardware device. Some of the issues that may arise with mismatches between assigned logical names and the physical labels associated with hardware devices in a network appliance are discussed with reference to FIG. 1. FIG. 1 illustrates a network appliance chassis portion 110 that provides a number of network cable receptacles 112. Each network cable receptacle 112 is provided with a physical label 120 that describes the expected logical name of a network port (not shown) connected to the respective network cable receptacle 112. Programmers and/or network technicians or other persons responsible for installing and maintaining the network appliance may often expect to depend upon physical labels 120 to indicate a respective logical name for each of the network ports that are connected to respective network cable receptacles 112.
However, as illustrated in FIG. 1, network ports connected to network cable receptacles 112 may be assigned logical names 130 that do not match respective physical labels 120. Such a mismatch or inconsistency in naming convention may typically occur due to the unpredictability of the order of discovery of hardware devices, such as network ports, by the OS in a network appliance, as discussed above. In the example of FIG. 1, a group of network cable receptacles 140, 141, 142 and 143 for Ethernet cable connections have respective physical labels 120 of Eth4, Eth5, Eth6 and Eth7. Network cable receptacles 140-143 are illustrated as belonging to a network interface controller (NIC) PCIe card 150 that occupies a PCIe slot indicated as Slot 0 in FIG. 1. The network ports associated with network cable receptacles 140-143 are the first discovered network ports, are determined to be Ethernet network ports, and are thus assigned respective sequential logical names 130 of Eth0, Eth1, Eth2 and Eth3, which do not match the respective physical labels 120 of Eth4, Eth5, Eth6 and Eth7. Accordingly, programmers and/or network technicians involved in maintaining or installing the network appliance may not be able to rely on the value of a logical name 130 being matched to a physical label 120 for a given network port and associated network cable receptacle 112.
Such a mismatch between assigned logical names 130 and physical labels 120 may result in a programmer and/or network technician being uncertain as to which network port is actually connected to a network cable inserted into a given network cable receptacle 112. In such a situation, the network ports involved in a naming mismatch may thus not operate as expected, which may lead to unpredicted behavior for the network appliance, or may cause the network appliance to appear to malfunction, for example. Network ports are sometimes assigned specific functionality in accordance with physical labels 120, which functionality might depend on the network port capability, physical location or intended usage. For example, two or more network ports with network cable receptacles 112 that are located near each other may be paired for a given task related to redundancy or link aggregation. In addition, the physical location of a given network cable receptacle 112 for a network port may implicate security functionality, such as for administrative or management operations. When the relationship between a logical name 130 and a physical label 120 of a network port is uncertain, the physical arrangement-dependent configurations described above may not function properly.
Some OS facilities may be available to modify the logical names of the hardware devices located by the OS, which modifications may be permitted to persist upon being implemented. These configuration changes may involve manual modification of system configuration files, and may depend upon OS type, OS vendor, OS version, NIC arrangement, NIC vendor or NIC version, for example. Such modifications might be applied to associate each desired network port with a desired logical name that matches a corresponding physical label. However, such modifications may involve a somewhat sophisticated understanding of the network appliance, NIC and/or the OS used to generate the new logical name assignment, so that the task is non-trivial. For example, an administrator making such a change may need to be aware of specific hardware addresses for the hardware device being reconfigured, which hardware addresses may differ among different manufacturers.
In general, it is not desirable to reassign the physical labeling of the hardware devices, such as network ports, to match the logical names of the respective hardware devices. The physical labels are typically fixed in place during manufacturing to resist being removed, while the logical name order can change based on a number of factors, so that even if physical labels are moved, they might not always reflect the desired relationship with a corresponding logical name for associated hardware devices. Accordingly, it is often left to the user of the network appliance to manually configure the logical names assigned by the OS to match those provided by the physical labels. Such a process tends to be complex and time consuming, and also might be repeated, for example, in the event of OS reinstalls or updates or hardware modifications as may occur with the addition, modification or removal of a pertinent hardware device.
Therefore, it would be desirable to permit hardware devices in a network appliance to be configured with logical names to match physical labels associated with the hardware devices to aid in the installation, configuration and/or maintenance of the network appliance.